Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Note 7 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		3 Months Ended
	Apr. 30, 2019	Jan. 31, 2018	Mar. 31, 2020	Mar. 31, 2019
Proceeds from Stock Options Exercised			$ 29	$ 356
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total			$ 557
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			1 year
Restricted Stock [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total			$ 107
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			1 year 328 days
Restricted Stock [Member] \| The 2014 Long-term Incentive Plan [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross (in shares)	20,000	17,500
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)	$ 11.12	$ 7.16
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)		3 years